Web
Browse 6 professional tools
HTML Entity Encoder
IP Subnet Calculator
Meta Tags Generator
URL Encoder & Decoder
Website Screenshot
What's My IP
Web tools cover the operational side of running things on the internet — URL encoding, IP / network math, meta tag generation, screen-capture, finding your own IP. Most are inspection and reference: when something does not render right on Slack, when CORS blocks your fetch, when a route does not match the way you expected.
Encoding
URL percent-encoding and HTML entity encoding are different despite looking similar. URL-encoding is for path segments and query strings; HTML entity encoding is for text inside HTML and prevents XSS. Using one where the other belongs creates injection bugs.
Encode and decode URLs online. Convert special characters to percent-encoding for safe URLs. Free URL encoder/decoder tool for developers
Encode and decode HTML entities online. Convert special characters like <, >, &, quotes to HTML entities. Free HTML escape/unescape tool
Networking
CIDR subnet math (network address, broadcast, usable host range, wildcard mask for Cisco ACLs). What's My IP shows your public IPv4 + IPv6 + LAN IP + ISP info — useful for whitelisting and verifying VPN routing.
Calculate IP subnets, network ranges, broadcast addresses, CIDR notation. IPv4 subnet mask calculator. Free online IP/CIDR calculator for network admins
Find your public IP address with geolocation, ISP, timezone info. Check IPv4/IPv6 address, hostname, browser details. Free online IP lookup tool
SEO & metadata
Open Graph + Twitter Card + Schema.org meta tag generation with size limits validated (title ~60 chars, description ~160). HTTP Status Codes is a reference; the interesting cases are 401 vs 403 (authentication vs authorization), 422 vs 400 (semantically invalid vs malformed), 410 vs 404 (intentionally gone vs unknown).
Generate SEO meta tags, Open Graph, Twitter Cards with live preview. Optimize website metadata for search engines and social sharing
Complete list of HTTP status codes with descriptions and examples. Learn 200, 301, 404, 500 error codes. Free HTTP response code reference guide
Capture & preview
Render any public URL at a specific viewport and capture PNG/WebP/PDF. Useful for Open Graph images, responsive design audits across breakpoints, archival snapshots.
Frequently asked questions
Should I percent-encode spaces as %20 or +?
In path segments: %20. In query strings: either works, but %20 is universal and + is application/x-www-form-urlencoded specific. Modern code: use the URL constructor or URLSearchParams; never hand-roll URL encoding.
Why does my CORS error not match the server response?
CORS is enforced by the browser, not the server. The server may return 200 with correct headers, and the browser still blocks the JS callback because of a mismatch (wildcard + credentials, missing Vary, missing preflight). Use the CORS Debugger to walk the algorithm step-by-step.
Is my public IP private information?
Partially. It identifies your ISP and metro area; not your home address. Persistent IPs can be tracked across sites (mitigated by IPv6 privacy extensions which rotate daily). VPNs replace your IP with the VPN provider's.
How long should I keep my meta description?
150-160 characters for desktop SERPs; ~130 for mobile. Width is in pixels, not characters — wide letters (W, M) reduce the visible count. Test against actual SERP snippets, not just character counters.
Last updated · E-Utils editorial team